In all honesty I feel it would be beneficial to keep your e-Bay ID private.The reason being many people on these types of forums sell on e-Bay and at times may be offering an identical item,you could be setting yourself up to have your auction sabotaged by those whom you think you can trust.
It has happened to me in the past so to be a bit safer I've decided to change my ID and keep it private from here on out.
I really think it's sort of silly to do post counts, a lot of posters post comments that don't really contribute to the thread like 'I LOVE IT!!!' when 50 other people before them already said the same thing (not that that's a bad thing!), but I personally tried to keep my posts longer to at least give a little contribution or in the very least express my opinion and give a reason why I like/dislike something.
For example, in college they tried to make you do essays or papers with a word count, and honestly I just created a situation where people wrote in a more wordy manner than usual.